Answer:
Angelina should buy 9 packs of pens and 8 packs of pencils.
Step-by-step explanation:
Each pack of pens = 8 pens
Each pack of pencils = 9 pencils.
Also we know that, Commutative Property of Multiplication states that
a x b = b x a for any two numbers a and b.
So, 8 x 9 = 72 = 9 x 8
Hence, she should buy 9 packs of pens, so she will have 9 x 8 = 72 pens.
And she should buy 8 packs of pencils, she will have 8 x 9 = 72 pencils.
Answer:
1.6x10^-18 gram
Step-by-step explanation:
(5.3 x 10⁻²³ gram/molecule) x (20,000 molecule)
= (5.3 x 10⁻²³ x 2 x 10⁴) gram
= (10.6 x 10⁻²³⁺⁴) gram
= (1.06 x 10⁻²³⁺⁵) gram
= 1.06 x 10⁻¹⁸ gram
We need to find the mass of 20,000 molecules of oxygen. It can be calculated using unitary method. Here, we can multiply 20,000 molecules by the mass of one oxygen molecule.
42
Step-by-step explanation:
<em>I added 11+12+10+9=42</em>
Answer:
1000
Step-by-step explanation:
Round the 6 in 600, this is 1 significant figure.6 rounds up to 10 making 1000
