Answer: 3136 feet
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Step-by-step explanation:
Plug in t = 6. In other words, replace every copy of t with 6. Afterward, you use PEMDAS to simplify
h(t) = -16t^2+192t+2560
h(6) = -16(6)^2+192(6)+2560 ... every t replaced with 6
h(6) = -16(36)+192(6)+2560
h(6) = -576+1152+2560
h(6) = 576+2560
h(6) = 3136