<span>A seatbelt should be fastened so as to run diagonally across the chest and to fit low and tight across the waist. This ensures that, during the rapid deceleration experienced during a crash, the seatbelt will perform the intended function, that is, to keep the passenger in place within the vehicle.</span>
All of the above are needed. Nucleotides are the basic building blocks of new DNA, ATP energy is needed because replication is an active process, and enzymes catalyze the reactions needed to carry it out (e.g. helicase to separate the strands to be replicated, DNA polymerase to build the new strands, and ligase to "glue" the fragments together).
All rock on the ocean floor is less than 180 million years old because <span>reverse polarity removed older rock strips magnetized in a different direction. Also,</span> the oldest parts reach the continental crust and then the ocean floor sinks beneath the continental crust, into the mantle.