1. That may be ascended.

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• zscendable,
• sscendable,
• wscendable,
• qscendable,
• aacendable,
• azcendable,
• axcendable,
• adcendable,
• aecendable,
• awcendable,
• asxendable,
• asvendable,
• asfendable,
• asendable,
• ascenable,
• acsendable,
• assendable,
• ascandable,
• aksendable,
• asceandable

• ascendency,
• ascendancy,
• ascendant,
• ascendance,
• ascendence,
• asyndetic,
• asunder,
• ascendible,
• ascendent,
• ascender,
• ascending.

The adjective form of "ascendable" is "ascendible" or "ascendible". Both spellings are acceptable.

The plural form of "ascendable" is "ascendables".

The singular form of the word "ascendable" is "ascendable". The word does not change in form from singular to plural.