MIS 310 can you plz break it down for me and what should been the answer??

A table named AIRPLANES already exists with columns as shown above. (note: column names in bold are NOT NULL) Which of the following SQL will successtully change the following 2 columns. 1. manufacturer which needs to be changed to varchar(50) and data is always required, and 2 variant for which data type does not need change but data is not always required. Selected Answers: ALTER TABLE AIRPLAARS ( UPDNTE CODUMN manufacturer VARCHAR(50) Nor NULT. 1 is ALTER TABLE AIRPLANES ( UPDATE COLUSA yariant chtrif(5) Nutit Question 2 A table named AIRPLANES already exists with columns as shown above. Column names in bold always require a value. Which of the following SOL. will successtully remove the column named rangeMiles Selected Answers: ALTER TABLE AIRPLANES DROP COLUMN [rangeNiles] ALTER TABLE AIRPLANES REMOVE COLUMN rangeMiles