Aformal accusation of a crime issued by a grand jury

Apeak with a retention time of 407 s has a width at half-height (w1/2) of 7.6 s. a neighboring peak is eluted 17 s later with a w1/2 of 9.4 s. a compound that is known not to be retained was eluted in 2.5 s. the peaks are not baseline resolved. how many theoretical plates would be needed to achieve a resolution of 1.5?

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How did planetesmals form planets? a. they broke apart into smaller chunks.b. they collided and stuck together.c. they cooled and pulled ice together.d. they began to rotate.