The relation between density, mass and volume is

1) to calculate = volume
given:
Density = 0.0915 g/ mL
mass = 17.7 grams
formula used:

Thus
Volume 
Answer: 193.44 mL
2) the mass of sample will be

Answer: 7 g
Answer:
2.44 K IS THE TEMPERATURE OF THE GAS
Explanation:
PV = nRT
P = 0.5 atm
V = 2 L
n = 5 moles
R = 0.082 L atm mol^-1 K^-1
T = ?
Substituting for T in the equation, we obtain:
T = P V / nR
T = 0.5 * 2 / 5 * 0.082
T = 1 / 0.41
T = 2.44 K
The temperature of the gas is 2.44 K