A 1.00-gram sample contains two radioactive isotopes A and B. The half-life of isotope A is 2 hrs. After 1 hr, the amounts of A and B in grams left in the sample are equal. After 3 hrs, the ratio of the amounts of A and B left in th sample is 5:3. a) What is the half-life of isotope B? b) What are the amounts of isotopes A andB in the initial sample?

Q: In the question as follows , use the weight of the rocket to answer each question. (Use 4000 miles…

A:

Q: II. Consider an object in a surrounding with constant temperature of 25°C. If the temperature of the…

A:

Q: Plain doughnuts from a particular bakery have an average mass of 32.6 g, whereas jam-filleddoughnuts…

A: Given, mass of plain doughnuts(m1)=32.6g mass of jam-filled doughnuts(m2)=40.0g (a). A dozen have…

Q: If two gases have molar masses M1 and M2, Graham's law states that the ratio R of their rates of…

A:

Q: 16. A chain lying on the ground is 10 m long and its mass is 80 kg. How much work is required to…

A:

Q: A water tank, open at the top, consists of a right circular cylinder and a right circular cone, as…

A:

Q: A candy company wants to produce 25 kilograms of a special 35% fat content chocolate to conform with…

A: Given: A candy company wants to produce 25 kilograms of a special 35% fat content chocolate.To…

Q: If the work required to stretch a spring 5 feet beyond its natural length is 15 foot-pounds, how…

A: first, we need to find the spring constant  W=∫0a fxdx here we have W=15 and a=5 feet 15=∫05 fxdx…

Q: According to building specifications and physical measurements, the maximum weight that foundation…

A: If x is directly proportional to y, then it can be written that x ∝y or x=ky. Here, k is the…

Q: From a basket of fruits 75 apples and 29 oranges are drawn. Do these figures confirm the hypothesis…

A: Given: Number of apples=75 Number of oranges=29

Q: Consider an object in a surrounding with constant temperature of 25°C. If the temperature of the…

A:

Q: A tank with rectangular base and sides and open at the top, is to be constructed so that its depth…

A:

Q: Water is pumped from a tank at constant rate, and no more water enters the tank. If the tank…

A: Given: The amount of water at 3:56 PM is 10452 L and amount of water at 4:12 PM on same day  is 8092…

Q: The area of a triangle with sides of lengths a and b and contained angle θ is A = 1 2 absinθ (a) If…

A: The area of a triangle with sides of lengths a and b and contained angle θ isA = 12absinθ   (a)…

Q: A silo consists of a cylinder surmounted by a hemisphere. If the floor is three times as expensive…

A: Let r be the radius of the hemisphere. This is also the radius of the base of the cylinder. Let h be…

Q: Based on the figure below, how much water is stored after 20 minutes in each of the tanks? How long…

A:

Q: certain culture of bacteria, the rate of increase is proportional to the numberpresent. (a) If it is…

A: (a) Consider y as the number of bacteria at time t and the rate of change of bacteria can be written…

Q: 4. A water tower is built in the shape of a right circular cylinder whose base is 10 meters in…

A: The tower is built in the shape of a right circular cylinder with base diameter 10 meters and…

Q: If two equal charges, each of 1 C, were separated in air by a distance of I km, what would between…

A:

Q: 2.18: When brought to the emergency room, an accident victim has 3 liters of blood and is still…

A: Let x(t) gltr be the amount of antibiotic drug.  rate in = 0.5 ltrhr0.5gltr=0.25ghrrate…

Q: Suppose you are a pharmacist and a customer asks you thefollowing question. His child is to receive…

A: Given: Total nausea medicine received by child=13.5 mlTotal time period=54 hours To Find: The amount…

Q: A cylindrical chemical storage tank with a capacity of 1000 is to be constructed and stood upright…

A: Given dimensions of warehouse is 12m by 15m and has a height of 11m and a cylindrical chemical…

Q: The intensity of illumination at any point from a light source is proportional to the square of the…

A: Given that The intensity of illumination at any point from a light source is proportionalto the…

Q: Two closed-lid tanks are connected in series. The first tank initially contains 100 grams of salt…

A:

Q: A large cube is formed from the material obtained by melting three smaller cubes of 3, 2, and 1 cm…

A:

Q: The length l of a rectangle is increasing at a rate of 7 cm divided by sec while the width w is…

A: Given:-             The length l of a rectangle is increasing at a rate of 7 cm/ sec while the width…

Q: A large cube is formed from the material obtained by melting three smaller cubes of 3, 2 and 1 cm…

A:

Q: 1.19 A water system of 2 in. (inside diameter) pipe, having a length of % mile, is to be flushed…

A:

Q: The side of a cube increases at a rate of 7 meter /second. Then the rate at which the volume of the…

A:

Q: If a substance decomposes at a rate proportional to the amount of the substance present, and the…

A:

Q: A group of fitness club members lose a combined total of 28 kilograms in 1 week. There are…

A:

Q: A 1000-kg car traveling at 35 m/s takes 3 m to stop under full braking. The same car under similar…

A: We have given  initial velocity u=35m/s, final velocity v=0  and taking time t=3m=180 s we know that…

Q: If the base radius of a cylinder increases over time, while its volume remains constant, will the…

A: Assuming radius r>0 and height h>0 , volume of cylinder V=πr2h Given: r is increasing over…

Q: 4. The volume of the fish tank needs to be tripled. 10 in 3 in 18 in What scale factor should be…

A: Given a fish tank whose volume has to be tripled. To find the scale factor

Q: Find how much more energy was released by an earthquake of magnitude 6.9 than by an earthquake of…

A: Solution: use formula Log E = 11.8+1.45M

Q: A tennis ball is dropped from a height of 8ft. If the ball rebounds 3 over 4 of its height on each…

A:

Q: 5. A farmer desires to irrigate a border which is 12 m wide and 150 m long. He wants to apply an…

A: Given: Width = 12 m Length = 150 mdepth of water=75mm =0.075mDischarge of stream  =60 l/sec

Q: A cardboard box with the dimensions of 20*15*5 (lwh), is used by a compnay to package laptops. If…

A:

Q: Two ships travelling from Dumaguete to Cagayan de Oro differ in average speed by 10 kph. The slower…

A:

Q: The smaller tank in the photograph has a capacity of 1400 m3​ ​and the larger tank has a capacity of…

A:

Q: an ice cube is shrinking uniformly at a rate of 8 cubic inches per hour. when the cube has a volume…

A: We are given the rate of change of volume of ice cube is shrinking uniformly at a rate of 8 cubic…

Q: The number of germs in a certain culture increases at a rate proportionai to the number present. If…

A: Given that, the number of germs in a certain culture increases at a rate proportional to the number…

Q: 1.MC IS FIVE TIMES AS OLD AS JUSTIN. FIVE YEARS AGO, MC WAS TWO TIMES AS OLD AS JUSTIN. THE SUM OF…

A:

Q: . A small metal bar, whose initial temperature was 20° C, is dropped into a large container of…

A:

Q: If you leave a 100-W light bulb on for a week, how many joules of energy will be consumed?

A:

Q: A tank contains 50 gallons of a solution composed of 90% water and 10% alcohol. A second solution…

A:

Q: A 25-liter gas cylinder contains 80% oxygen and 20%   helium. If helium is added at a rate of 0.2…

A: The volume of cylinder =25 litre The percentage of oxygen in the cylinder initially=80% The amount…

Q: C. A circular swimming pool has a diameter of 6 m, the sides are 1.5 m high, and the depth of the…

A: Use formula of work done

Q: A 5 cm cube is cut into as many 1 cm cubes as possible. What is the ratio of the surface area of the…

A: A 5 cm cube is cut into as many 1 cm cubes as possible. Length of an edge of larger cube is 5 cm and…

Q: If =1 cu cm (not actual size), how many cu cm will be needed to fill each bo 1. 2. 3. volume = cm3…

A: