Examine the following equations.

A. 23490Th→23491Pa+0-1e+γ

B. 60∗27Co→6027Co+γ

C. 23490Th→23088Ra+42He

D. 146C→147N+0-1e

Which equation or equations represent gamma decay?

A and D

D

C

C and D

A

A and B

B

Radioisotopes tell scientists that Earth is how old? A. 65 million years B. 500 million years C. 4.5 billion years D. 13.4 billion years

What is the total number of valence electrons in a calcium atom in the ground state? (1) 8 (3) 18 (2) 2 (4) 20

How does density connect to the layers of the earth?

What distance will a truck travel in 3 hours at an average speed of 50 miles per hour?

A water tank has a mass of 3.64 kg when it is empty and a mass of 51.8 kg when it is filled to a certain level. what is the mass of the water in the tank?

If a spoon is hot after leaving it on the pot that was on the stove. What heat transfer is that.

If a small amount of ferrous ammonium sulfate is spilled when transferring

List one reason as to why historical growth has slowed in recent years.

Name some specific liquids that you think might contain less than 80 percent water.

The ostwald process is used commercially to produce nitric acid, which is, in turn, used in many modern chemical processes. in the first step of the ostwald process, ammonia is reacted with oxygen gas to produce nitric oxide and water.