Net the condor, then move the market

You buy a call with delta 0.30 and sell a call with delta 0.45 on the same underlying and expiration, one contract each. What is the spread's net delta per share?

• +0.75
• −0.15
• +0.15

Which sign does a short option contribute to a position's theta and vega?

• Negative theta and positive vega
• Positive theta and negative vega
• Positive theta and positive vega