Select all of the true statements (there may be more than one correct answer).
a. {a1,a2,a3} is a linearly independent set
b. {a1,a2} is a linearly independent set
c. {a1,a2,a3,a4} is a basis for r3
d. span{a1,a2,a3}=r3 e.
{a1,a2,a3} is a basis for r3 f.
span{a1,a2}=r3 g. {a1,a2,a3,a4} is a linearly independent set h.
span{a1,a2,a3,a4}=r3 i. {a1,a2} is a basis for r3