A ball thrown upwards hits a roof and returns back to the ground. The upward movement is modelled by a function s=−t^2+3t+4 and the downward movement is modelled by s=−2t^2+t+7, where s is the distance (in metres) from the ground and t is the time in seconds.

Find the height of the roof from the ground.

Give your answer as a number without units.

Peaches cost $4.29 per pound. find the cost of two and a quarter pounds of peaches.

Explain how you can find the missing fraction in 3 4/5 / (blank) 2 5/7. then find the missing fraction.

Three friends went on a road trip from phoenix, az, to san diego, ca. mark drove 50 percent of the distance. jason drove 1/8 of the distance. andy drove the remainder of the distance. 1. andy thinks he drove 1/4 of the distance from phoenix, az, to san diego, ca. is andy correct? 2. the distance from phoenix, az, to san diego, ca, is 360 miles. how many miles did each person drive? 3. solve the problem. what is the answer in total?