Which is an equation of a direct proportion?

a. y=1/3x-2

b. y=3/x

c. y= -3x+4

d. y=3x

Geometry. i need step by step explanation on how to do each problem.

Order the measurements from the least to the greatest. 2,720 ml , 24.91 l , 0.0268 kl

Neoli is a nurse who works each day from 8: 00 am to 4: 00 pm at the blood collection centre. she takes 45 minutes for her lunch break. on average, it takes neoli 15 minutes to collect each sample and record the patient's details. on average, how many patients can neoli see each day?