Graeco-latin square is a form of blocking by one variable. a form of blocking by four variables. a form of blocking by three variables. a form of blocking by two variables.

A form of blocking by three variables.

Step-by-step explanation:

Graeco-Latin square design is a special type of comparative design.

Graeco-Latin square design uses 3 blocking variables unlike the 2 blocking variable as used by the standard Latin square design.

In this square design of experiment, the experimental units are grouped into three different ways.

option c) graph of line going through 1, 4 and 3, 10

step-by-step explanation:

let y equal to margo's coin collection

let x equal to number of years

at the begining x=0, y=1 → point=(x,y)→point=(0,1)

she adds 3 coins per year, then y=1+3x

at x=1, y=1+3(1)=1+3→y=4→point=(x,y)→point=(1,4)

at x=3, y=1+3(3)=1+9→y=10→point=(x,y)→point=(3,10)

the graph of line going through (1, 4) and (3, 10), then the option c is the correct.