Jim measures the count rate of a sample of americium-241 as 120cpm. Roughly how long would it take for the count rate to fall below 4 cpm. Show your working

Which planet has the highest average surface temperature, and why? a. Mercury, because of its dense carbon dioxide atmosphere. b. Venus, because of its dense carbon dioxide atmosphere. c. Mercury, because it is closest to the Sun. d.

After a short time, an equilibrium is reached between the diffusion currents (also called recombination currents) and a second, opposing type of current. what causes these secondary currents?

Give 3 visible examples of motion that is caused by forces from living things

The pressure in a fluid is affected by which characteristic of that fluid? A. The weight of the fluid B. The gravity of fluid C. The amount of oxygen atoms in the fluid D. The amount of hydrogen atoms in the fluid

How are chargeable cells different from ordinary dry cells

How can you tell one element from another?

Which of the following is not an accurate statement about the attitude of teenagers when driving

the circumference of Earth's orbit is 938 million kilometres how fast does earth travel in km/h in one year

A material is said to be ductile if it

A professional soccer player succeeds in scoring a goal on 84% of his penalty kicks. assume that the success of each kick is independent.