So its acquired immunity and the cells responsible are the B lymphocytes that produces antibodies against the virus. Memory is keep since first encounter of the virus by the immune system by way of the antibodies that was initially produced. The antibodies are there already, which makes it fast to act upon when expose again.
The answer is D delusions breathing just took the test
The answer is blood flow will be reduced and will pool in the muscles.
At least 60 minutes a day
