Answer:
15000N/m²
Explanation:
Given parameters:
Force exerted by the girl = 450N
Area = 300cm²
Unknown:
Pressure exerted by her feet =?
Solution:
Pressure is the force per unit area on a body;
Pressure = 
We need to convert the given area to m²;
10000cm² = 1m²
300cm² = 
= 0.03m²
Pressure = 
= 15000N/m²
6.02*10^23 is Avagadro's number representing the number of molecules per mole of substance.
Answer:c
I need at least 20 characters to post
Answer:
Number of moles = 0.92 mol
Explanation:
Given data:
Mass of CaSO₄ = 125 g
Number of moles of CaSO₄ = ?
Solution:
Formula:
Number of moles = mass/ molar mass
Molar mass of CaSO₄:
Molar mass of CaSO₄ = 40 + 32+ 16×4
Molar mass of CaSO₄ = 40 + 32+ 64
Molar mass of CaSO₄ = 136 g/mol
Number of moles:
Number of moles = mass/ molar mass
Number of moles = 125 g/ 136 g/mol
Number of moles = 0.92 mol
