Not sure how to answer question 4

Option D is correct

Step-by-step explanation:

Applying the cosine theorem for triangle ABC, you would have:

cos (angle BAC) = (BA^2 + CA^2 - BC^2)/(2*BA*CA)

                           = (10^2 + 18^2 - 20^2)/(2*10*18)

                           = 24/360

=> angle BAC = ~86 deg

Hope this helps!

true

step-by-step explanation:

answer: 80,000

step-by-step explanation:

the population doubles every day.

10,000*2=20,000 day 4

20,000*2=40,000 day 5

40,000*2=80,000 day 6