Answer:
Factors that affect the speed of a river include the slope gradient, the roughness of the channel, and tides.
Explanation:
(B) because if you have areas that are infected with bacteria and that to swell it could kill a person
If a student made a model of an onion skin cell using a microscopic magnification scale of 500:1 and the length of the modeled cell is 15 cm, the real cell's length would be 0.03 cm.
The scale is 500:1. This means that the dimension of the real cell without being magnified under the microscope would be 1/500.
Thus, if the length of the cell under the microscope is 15 cm. This length has been multiplied by 500. In order to get the real length, it must be divided by 500.
15 x 1/500
= 0.03 cm
More on microscopic magnification can be found here: brainly.com/question/14668612