Please do it in excel and show the formulas

Suppose a firm's asset is $8 billion, while the upcoming debt amount to be paid is $10 billion in a month. The managers of the firm maximize the equity value. There are two projects available to invest in the meantime. (P1) A riskless project A with a positive net present value (NPV): If investing $1 billion today, the project returns $2 billion for sure in a month. (P2) A risky project B with a negative NPV: If investing $1 billion today, it returns $7 billion with probability of 50% and $7 billion with probability of 50% in one month. While ignoring the 1-month time value of money, clearly answer the following two questions: a. Which project among the two would the firm's managers choose and why? b. Under the project choice in part (a), what are the firm's equity and debt values, respectively