What is twos complement?

In single precision (IEEE-754 standard), 8 bits are used for storing the exponent (the bias is 127), and 23 bits are used for storing the mantissa.  (a) What are the smallest and the largest positive numbers that can be stored in single precision? (b) What is the smallest value of the mantissa that can be stored?

Complete the following arithmetic operations in two's complement representation. What are the values of the carry and overflow flag? Assume a six-bit system. 9 + (-19) = ?

Floating-Point Representation. What is the floating-point value for binary 4. a) 11000010100000 using the simple model (14-bit format, 5 bits for the exponent with a bias 15, a normalized significand of 8 bits, and a single sign bit for the number)?