权利是可能的，义务是必须的。

—_____ the blackboard! What can you _____ on it? [ ]

A. Look, look

B. See, see

C. Look at, see

D. Look, see

Financial information for Jefferson Corp. for the year ended December 31^st, was as follows:（）

A．Sales

B．$ 3000000

C．Purchases

D．1800000

E．Inventory at Beginning

F．500000

G．Inventory at Ending

H．800000

I．Accounts Receivable at Beginning

J．300000

K．Accounts Receivable at Ending

L．200000

M．Other Operating Expenses Paid

N．400000

如果1升汽油可行驶90km，那么驾车行驶99km，需要汽油______L．

履约保函的担保金额应在工程合同中规定，一般为合同总金额的()。

A.5% 

B.10% 

C.15% 

D.20%

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