Number three is D and number 4 is also D.
Explanation for number three:
When you divide 12 by 3, you get 4. This gives us the number we need to multiply 10 by to get our answer. 10 x 4 = 40
Explanation for number 4:
In the last question, the first step to getting to the answer was to divide the first two numbers. This is no different. When you divide 32.5 by 5, you get 6.5. Then you multiply 10 and 6.5, which equals 65.
Divide it by 4/4. You should get 7/8. 7/8 is the same as 28/32. 28/4=7, 32/4=8. Therefore, you can divide it by 4/4.
We presume the temperature is decreasing at midnight, so reaches a low at 6 a.m.. The amplitude of the variation is (87-63)/2 = 12 degrees. We want the period to be 24 hours, so the argument of the sine function will be 2π(t/24) = πt/12. Then we can write
... d = 75-12sin(π·t/12)
