70 points. Select the correct answer.
Which relation is a function?
(Look at the photo)

Option D didn’t fit in the photo, so here’s it typed out.

x | y
10 15
20 25
8 30
20 35

A is a function.

Step-by-step explanation:

All the others are one-to-many relations.

For example in B, 3 maps to 10 and also maps to 30 ( one - to - many).

A function is a one-to-one or many-to-one mapping.

Step-by-step explanation:

Options B, C and D have repeat x-values with different y-values.

The relationship is many-to-one.

If graphed, those point appear on a vertical line.

Option A has one-to-one relation, so is the only functional relationship

54 kilometers per hour

step-by-step explanation:

according to rules:

1 km = 1000 meter

which means that 1 meter = 1/1000 km

1 hour = 3600 second [ as 1 hour = 60 min = 60 *60 seconds ]

which means that 1 second = 1/3600 hour

therefore, 1 kilometer/hour =

thus to convert 15 meter per second to kilometer per hour, we multiply 15 to 3.6 kilometer/hour.

15 meter/second=   which is the required answer.