Respuesta :

Willchemistry
Molar mass  helium gas :

He = 4.0 g/mol

number of moles:  3.75 / 4.0 => 0.9375 moles

1 mole ------ 22.4 ( at STP)
0.9375 ------ ?

volume = 0.9375 x 22.4 / 1

Volume = 21 / 1

Volume = 21 L

hope this helps!