Health , ! alan chooses not to wear sunscreen because the oils build up on his skin. what is alan trying to prevent, and what is he failing to prevent? a. alan is trying to prevent skin cancer but failing to prevent acne. b. alan is trying to prevent acne but failing to prevent skin cancer. c. alan is trying to prevent psoriasis but failing to prevent eczema. d. alan is trying to prevent eczema but failing to prevent psoriasis.

What is the main structural difference between enveloped and nonenveloped viruses? a) enveloped viruses have their genetic material enclosed by a layer made only of protein.b) nonenveloped viruses have only a phospholipid membrane, while enveloped viruses have two membranes, the other one being a protein capsid.c) enveloped viruses have a phospholipid membrane outside their capsid, whereas nonenveloped viruses do not have a phospholipid membrane.d) both types of viruses have a capsid and phospholipid membrane; but in the nonenveloped virus the genetic material is between these two membranes, while in the enveloped virus the genetic material is inside both membranes.