Mistake in advanced management acc rtp nov2011?

Question number 3 in the AMA RTP for Nov2011 (Paper 5) 

The solution has New stock of B purchased at replacement cost of 30..however in the question it is given as 35..is it a mistake..or am i overlooking something? 

Question Number 2 in the same paper.

The solution states that the Less Fixed Factory Overhead is 7.5. how did they arrive at this figure? 50% of fac overhead is fixed..ie 50% of 30 = 15.and 70% gets eliminatied out of this 15..ie 10.5..so remaining should be 4.5..again..am i making a mistake?

please help soon..thanks a lot in advance..the rtp is attached.