Answer:
a country, state, or territory ruled by a king or queen.
The Earth is around 4.6 billion years old. Earth has a slightly squashed sphere, measuring 7,973 miles (12,756 km) in the diameter at the equator.
Answer:
Option D, A subject is observed both before and after two exposures to the treatment.
Explanation:
In A-B-A-B design the alphabets have following meaning
a) First A – It is the baseline value or the value measured before treatment
b) First B – It is the treatment measurement
c) Second A - It is the withdrawal of treatment
d) Second B – It is the reintroduction of treatment
The second A is known as the reversal phase in which the intervention is withdrawn to see if the target behavior returns to the baseline behaviour
Thus , there are two measurements involved one before the intervention and second after the intervention
Option D is correct
I believe it is gel electrophoresis.
Gel electrophoresis is a techniwue used to separate DNA fragments or other macromolecules such as RNA and proteins based on their size and charge. It can also determine the actual size of a piece of DNA by examining it next to a standard "yardstick" made up of DNA fragments of known sizes.