Question 1:

>> help linspace

 LINSPACE Linearly spaced vector.
    LINSPACE(x1, x2) generates a row vector of 100 linearly
    equally spaced points between x1 and x2.
 
    LINSPACE(x1, x2, N) generates N points between x1 and x2.
 
    See also LOGSPACE, :.

Question 2:

x = linspace(1, 10, 10);

Question 3:

~= is the boolean "not equals" operator. It can be used to compare integers, characters, and floating point numbers.

Question 4:

>> t = linspace(0,100,101);
>> x = t.^2;
>> y = sin(t);
>> plot(x,y);