Amanda says that a human fingernails has a thickness of about 4.2 x 10^-4 meter. justin says that a human fingernails has a thickness of about 0.42 millimeters .

what is the width in meters written in standard notation?

do justin’s and amanda’s measurements agree? explain .

explain why justin’s estimate of the thickness of a human fingernail is made appropriate than amanda’s estimate.

See below

Step-by-step explanation:

1. Standard notation

4.2 × 10⁻⁴ m

A negative exponent indicates

4.2 × 10⁻⁴ tells you that the decimal number is 4.2, with the decimal point moved four places to the left.

The number becomes 0.000 42 .

2. Metres to millimetres

3. Measurements agree?

Yes, because both measurements are the same as 0.42 m.

4. More appropriate measurement

Most measurements should be expressed as a number between 0.1 and 1000, because most people aren’t particularly good at visualizing larger or smaller numbers.

Justin's measurement of 0.42 mm is more appropriate than Amanda's measurement of 4.2 × 10⁻⁴ m.

mr. flanders’ class sold 47 doughnuts and   mr. rodriquez’s class sold 38 cartons of milk

step-by-step explanation:

let x be the number of doughnuts sold by mr. flanders’ class and y be the number of cartons sold by mr. rodriquez’s class.

1. together, the classes sold 85 items, then

x+y=85.

2. both classes earn earned $104.49 for their school. if doughnuts were sold for $1.35 each, then x doughnuts costed $1.35x. if cartons of milk were sold for $1.08 each, then y cartons costed $1.08y. hence,

1.35x+1.08y=104.49.

3. solve the system of two equations: