A meteorologist found that the rainfall in Belleville during the first half of the month was 3/8 of an inch. At the end of the month, he found that the total rainfall for the month was 1/2 of an inch. How much did it rain in the second half of the month?

1/8 in.

Step-by-step explanation:

The amount of rain in the second half of the month is the difference between the two amounts of rain.

1/2 in. - 3/8 in. = 4/8 in. - 3/8 in. = 1/8 in.

1/8 in.

the solution of the equation is 2.23 ⇒ answer b

step-by-step explanation:

* lets revise the meaning of exponential function

- the form of the exponential function is y = ab^x, where a ≠ 0, b > 0 ,  

  b ≠ 1, and x is any real number

- it has a constant base b

- it has a variable exponent x

- to solve an exponential equation, take the log or ln of both sides,  

  and solve for the variable

* lets solve the problem

∵

- the base is 7 and the exponent is x

- insert ㏑ in both sides

∴

- use the rule

∴ x ㏑(7) = ㏑(77)

- to find x divide both sides by ㏑(7)

∴

* the solution of the equation is 2.23 to the nearest 2 decimal places