5 years older...cause if David is 2 years younger than Graham & Neil is 7 years younger than Graham...7-2=5 years :)
Answer: The Answer is <u>A: 7.685</u> but then round it up to <u>8</u> on edge
Using scientific notation, it is found that:
67 ns =
s
<h3>What is scientific notation?</h3>
A number in scientific notation is given by:

With the base being
.
In this problem, the amount is of 67 ns.
Each ns has
seconds, hence:

We want the base between 1 and 10(exclusive), hence, we move the decimal digit one digit to the left and add one to the exponent, and the representation is:
67 ns =
s
You can learn more about scientific notation at brainly.com/question/16394306
7+5=12 so it can be one of these 8+4=12, 9+3=12, 10+2=12, and 11+1=12.
Equation::
value + value = value
80x + 60(50-x) = 74*50
----
80x + 60*50 - 60x = 74*50
----
20x = 14*50
x = 35 lbs (amt. of 80 cent tea to use)
50-x = 15 lbs (amt. of 60 cent tean to use)