may i please be advised regarding

from vb6 back ground to be away from vb6;
purpose:- to take some bachelor exam

(1) is it necessary to learn C first so as to learn C++
(1a) should i have to start right from C
(2) is C is a case sensitive language
(3) is C is having any IDE like VB
(4) why it is in the peoples mind that C is sea, unlike VB
(5) the right knowledge to be known to become a C programmer i mean, is should i have to know Algorithms,matrix,algebra,integration ... etc

your advises please..