2v−6v+7v=15 i need answer

Hassan bought a package of tofu. the temperature of the tofu was 14° celsius when hassan put the package into the freezer. he left the tofu in the freezer until it reached –19° celsius. which expressions explain how to find the change in temperature, in degrees celsius, of the package of tofu? select three that apply.

Atourist boat is used for sightseeing in a nearby river. the boat travels 2.4 miles downstream and in the same amount of time, it travels 1.8 miles upstream. if the boat travels at an average speed of 21 miles per hour in the still water, find the current of the river.

The 7th grade has collected $200 for a field trip that would cost $600. the teachers decided to ask $50 from additional students to cover the cost. how mny students must pay to cover the cost ? a 16studentsb 80studentsc 160studentsd 8students show work