The first one is 4 x 10^-9
second one is 4 x 10^10
third one is 5 x 10^7
fourth on is 2 x 10^-5
Go on this web operation calcularter
Just simply use the calculation of a trapazium.
[ (6+7) + 21 ][6]
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2
that's the formula of a trapazium. add the top length and bottom length, multiply it by the height and divide all of them by 2.
now the answer should be A, 102.
Answer:
The rock will be be 5 meters from ground level at time = 3.713 seconds
Step-by-step explanation:
As we know-
![s(t) = -4.9 * t^2 + v_0t + s_0](https://tex.z-dn.net/?f=s%28t%29%20%3D%20-4.9%20%2A%20t%5E2%20%2B%20v_0t%20%2B%20s_0)
V0 = velocity
S0 = height above ground when thrown
Substituting the given values, we get -
![9 = -4.9* t^2 + 12 * t +32\\-4.9*t^2 +12*t + 23 = 0](https://tex.z-dn.net/?f=9%20%3D%20-4.9%2A%20t%5E2%20%2B%2012%20%2A%20t%20%2B32%5C%5C-4.9%2At%5E2%20%2B12%2At%20%2B%2023%20%3D%200)
As per the formula
![t = \frac{-12+ \sqrt{12^2 -4*(-4.9)*23} }{(2*(-4.9)} \\t = 3.713](https://tex.z-dn.net/?f=t%20%3D%20%5Cfrac%7B-12%2B%20%5Csqrt%7B12%5E2%20-4%2A%28-4.9%29%2A23%7D%20%7D%7B%282%2A%28-4.9%29%7D%20%5C%5Ct%20%3D%203.713)
The rock will be be 5 meters from ground level at time = 3.713 seconds