First u multipl 3 times 3 then 9 times 4 I think which is 36
Answer: After 8 hours the pressure will be at -60?
Explanation: not sure how the balloon can reach -60 kilopascals but 15% of 300 is 45 and 45 x 8(hours) is 360. 300 - 360 is -60
600,00 + 40,00 + 700 + 30 + 9 is 640,639 in expanded form
![\bf \measuredangle DFC=\cfrac{1}{2}(\widehat{BG}+\widehat{CD})\implies \measuredangle DFC=\cfrac{\widehat{BG}+\widehat{CD}}{2}](https://tex.z-dn.net/?f=%5Cbf%20%5Cmeasuredangle%20DFC%3D%5Ccfrac%7B1%7D%7B2%7D%28%5Cwidehat%7BBG%7D%2B%5Cwidehat%7BCD%7D%29%5Cimplies%20%0A%5Cmeasuredangle%20DFC%3D%5Ccfrac%7B%5Cwidehat%7BBG%7D%2B%5Cwidehat%7BCD%7D%7D%7B2%7D)
you know what the arcCD is, and what the angle DFC is, so
solve for the arcBG