I just need the first one

Creation of an unnaturally uniform sample to represent a diverse populationcan be avoided by: a. including only willing b. asking another scientist for .c. choosing only identical participants.d. selecting individuals at random.

Which units ate used to measure both velocity and speed? check all that apply

Matthew decided he wanted to hike up mount everest. on his way to the top, it began to snow and the temperature dropped to -10°f. matthew forgot to wear a heavy jacket so his body began to shiver beyond control. in this case, matthew's body shivering is the to a drop in temperature. * 0 points reflex stimuli responce environmental facto