Respuesta :
					                   okay.consider  A as  the length of a text message conversation.
p(a>3)=1-p(b<3-2)/0.5)=1-0.97725= 0.02275.
hope i help.
good luck!
					                
					             p(a>3)=1-p(b<3-2)/0.5)=1-0.97725= 0.02275.
hope i help.
good luck!
 
			                   
					                  